Fuse.



No. 737,254. PATENTEVD AUG. 25, 1903.

W. LLLOYD. FUSE. Arrmonlonrurn SEPT. 9, 1902.

10 MODEL.

WILLIAM 'J. LLOYD,

ZIo. 737,254.

UNITED STATES Patented August 25, 1903.

PATENT OFFICE.

WVILLIAM J. LLOYD, OF PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO STANLEY ELECTRIC MANUFACTURING COMPANY, OF PITTSFIELD, MASSACHUSETTS, A CORPORATION OF NEW JERSEY.

Fuse.

SPECIFICATION forming part of Letters Patent No. 737,254, dated August 25, 1903.

Application filed September 9, 1902". Serial No. 122.726. (No model.)

in its action and also convenient in manip ulation. To this end I construct the fuse so that the portion at which the break takes place is exposed to the air, the terminals of the fusible strip being submerged in oil. The device is further so constructed that when .the fusing takes place the remaining portions of the fusible strip are at once submerged in oil or similar non-conducting liquid, and so as to be safely handled and adjusted.

The following is a description of my invention, reference being had to the accompanying drawings, in which- Figure 1 is a plan view of the device. Fig. 2 is a longitudinal section of the same on the line 00 00, Fig. 3. Fig. 3 is a cross-section of the same on the line 3 :1 Fig. 2. Fig. 4 is a detail view of the fusing-strip.

Referring more particularly to the drawings, A is a cast-iron box with two offsets B B. In the bottom of the cast-iron box is supported an insulating-platform O. This insulating-platform O carries mounted upon it two contact-jaws D D. Electrically connected to the contact-jaws D D are the two leads E E, which project from the cast-iron box through the offsets B B. These leads E E areinsulated from the box A by the porcelain tubes F F, extending from the outer end of the offsets nearly to the terminals on the jaws D D.

The lid R of the cast-iron box is removable, being held in position by retaining -springs G G. This lid has attached to it two insulating posts or pedestals H H; carry at their ends switch jaws or contacts I I, engaging with the jaws D D when the lid is on the box. The switch-contacts I I are also electrically connected to fuse-terminals J J, to which is fastened the fuse-strip K. The lid of the box also carries an insulating- These posts bridge L, over which the fuse K extends. The box A is filled with oil or other non-conducting liquid to such a point that when the lid is in place the level of the liquid reaches just to the bottom of the porcelain bridge L.

Attached to the fuse contacts J J are springs M M. Thefree ends of these springs press down on the fuse-strip K.

The fuse-strip can be made of any desired fusible metal. The shape best adapted for use with this apparatus is shown in Fig. 4, the narrow part being that which reaches across the bridge K. The wide portion of the strip is the part which reaches from the contacts J J to the bridge L. By this construction the portions of the fuse'strip under the oil have a large carrying capacity, and hence generate Very little heat. This feature is very important, for if portions of the fusestrip beneath the oil got very hot the oil would boilaway.

The construction of the porcelain bridge L is such that the narrow portion of the fusestrip is supported in the airthat is, the upper surface of the bridge is recessed, as shown, so as to leave the fuse supported upon ridges at each side. This feature also is important, as it has been demonstrated by experience that the fuse metals are more uniform in their action when the strips are supported freely in the air.

Between the terminals B B and fastened to the insulating-platform C is an upright insulating-partition N, acting to more effectually separate the terminals after the fuse is blown, as will hereinafter be seen.

The lid of the box is held in position by spring guides and clips G G.

The action of the apparatus is as follows: Suppose a current sufficient to melt the narrow portion of the fuse-strip K to flow from terminals J to J. The fuse-strip immediately ruptures. The springs M M being under tension press the remaining portions of the fuse-strip down and the ruptured ends of the fuse are pushed beneath the oil and the are put out. The partition N preventsthe ends of the two portions from meeting under the oil. To replace the broken fuse, the cover is taken off the box A,carrying with it the fuse- ICO contacts, springs, and bridge. The new fuse is bolted to the contacts J J, the strip being passed over the bridge K and the springs being placed upon the strip. The cover is then replaced, which causes the terminals J J to be electrically connected with the jaws D D,

which are in turn connected to the external circuit.

It will be seen from the above that the fuse has the advantage of being ruptured at a portion exposed to the air and that the device acts to extinguish the arc at once by submerging the separate portions in oil and that the insertion of a new fuse is a simple and safe operation, the only parts which it is necessaryto handlebeingentirelyremovable from the circuit and replaceable without in any way coming in contact with the line.

In order to reduce the explosive action of the burning of the oil fumes, the bottom of the porcelain bridge L is made solid, so that the are for the fuse when it burns will not be on the surface of the oil and cause it to volatilize. There are also provided vent-holes r in the cover R, as shown, to permit the pass ing away of fumes which may be formed.

WVhat I claim as my invention is- 1, In combination, a strip of fusible metal having a raised portion supported on a bridge having ridges, terminals for said strip, alayer of insulating liquid covering said terminals but not said raised portion, and means for depressing the parts of said strip when the raised portion has been fused.

2. In combination, a vessel, a layer of insulating liquid therein, terminals beneath the surface of said liquid, and a fusible strip connected to said terminals having a reduced portion supported above said liquid on a bridge having ridges and enlarged portions beneath said liquid.

3. In combination, a vessel, a layer of insulatin g liquid therein, a detachable cover carrying terminals submerged in said liquid, a fusible strip attached to said terminals having a portion raised above said liquid, submerged contacts connected to the outer circuit, an insulated partition between said contacts, and means for detachably engaging said terminals with said contacts.

4. In combination a vessel, a layer of insulating liquid therein, a detachable cover carryingterminals, submerged in said liquid, a fusible strip attached to said terminals having a portion raised above said liquid, submerged contacts connected to the outer circuit and means for detachably engaging said terminals with said contacts.

5. In combination avessel, a layer of liquid therein, terminals submerged in said liquid, a fusible strip connected to said terminals having an unsubmerged portion and a bridge having ridges for supporting said unsubmerged portion.

6. In combination a vessel, a layer of liquid therein, terminals submerged in said liquid, a fusible strip connected to said terminals having an unsubmerged portion, a bridge for supporting said unsubmerged portion and an insulating-partition between said terminals.

Signed at Pittsfield, Massachusetts, this 2d day of September, 1902.

XVILLIAM J. LLOYD. lVitnesses O. H. P. FAUT,

LEONARD WILsoN. 

